Typical weapons systems are comprised of a weapon mounted onto a mount to a moving vehicle that allows the operator to slew the weapon in elevation and azimuth. These systems can be used to provide defensive suppression fire. Additionally, many of these systems, when employed from airborne platforms, can be used to provide close air support (CAS) where accuracy is extremely important due to the close proximity of friendly forces to enemy combatants.
A typical system is operated by a single gunner whom identifies and locates a threat through unaided vision. At night, this is accomplished usually using Night vision Goggles. However, the detection is limited to the range of the gunner's eyesight. At night the problem of identifying enemy targets is even greater due to the fact that enemy combatants are aware of the limitations with Night Vision Goggles.
Once the gunner identifies a threat, the gunner looking down the barrel of the weapon must compensate for the motion and speed of the moving vehicle when firing the weapon. This usually requires the gunner to fire bursts of ammunition from the weapon to “walk” tracers onto the target.